MILLBRAE — The San Mateo County Sheriff’s Office announced Friday night it has launched an internal investigation to learn why two previous probes of a Millbrae teacher suspected of having a sexual relationship with a student were not conducted in a “timely manner.”

The effort follows 40-year-old Heather Amanda Butts’ arrest by San Bruno police on Aug. 17, two days after they responded to a tip about a woman who was “engaged in inappropriate behavior” with a girl in a car parked on Santa Helena Avenue in San Bruno.

Butts, who teaches at Taylor Middle School in Millbrae, is suspected of lewd and lascivious acts involving a child and communicating with a child with the intent to commit a crime.

In a statement Friday, the Sheriff’s Office said it only recently “became aware that two reports of a Millbrae teacher having a sexual relationship with an underage girl were not investigated as expected.”

One probe was launched in October and another in February, according to the statement.

“I’m disappointed the investigation was not completed in a timely manner and it does not reflect the level of service we routinely provide the residents of Millbrae or the communities we serve,” said Sheriff Carlos Bolanos.

According to a report by ABC7 News, this newspaper’s media partner, the Millbrae School District also may have known about the alleged sexual relationship between Butts and the student.

A parent told the station he filed a police report in October and then notified district officials in February. The dean of students told the parent the district was aware of the police report; however, Butts continued to teach up until her arrest, according to ABC7 News.

Superintendent Vahn Phayprasert could not be immediately reached for comment Friday night.

In a statement last week, Phayprasert said the district had placed Butts on leave and was cooperating with the police investigation.

“The district has policies and procedures in place to help ensure the school operates in a safe environment and we are constantly looking for ways to enhance those policies and procedures,” the superintendent said. “The safety of our students is the highest priority.”

Butts, who is out of custody on bond, is slated to return to court for an arraignment Sept. 19.

Jason Green is a breaking news reporter for the Bay Area News Group. He works week nights and spends most of his time covering crime and public safety. A graduate of UC Santa Barbara and the University of Southern California, he cut his teeth at the Inland Valley Daily Bulletin and the Palo Alto Daily News, and has been with the Bay Area News Group since its inception.

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